Regarding designs of output stage circuits, most of circuitry adopts a push-pull scheme for purposes of high speed and high efficiency. Concerning one of advantages of the push-pull scheme, the push-pull scheme can achieve almost a rail-to-rail output. Therefore, the push-pull scheme has high efficiency and is easily integrated into IC (integrated circuit). A significant trend throughout integrated circuit (IC) development is the downsizing of IC components. As the size reduces, the performance requirements become more stringent. Also, as devices continue to shrink in size, the channel region continues to shrink as well. For metal-oxide-semiconductor field effect transistors (MOSFETs), increased performance requirements have generally been met by aggressively scaling the length of the channel region. However, such a short channel length or scaling down faces problems of decreasing breakdown voltages. Ranges of output voltages are limited to characters of processing or physical restriction of devices. It becomes harder to utilize devices having low breakdown voltages into systems where output voltages are much higher than breakdown voltages of each devices.